[Snake]

I think this skill could probably just stand having enchantment apply at half effectiveness (+2 rounds) and having it be able to apply to Swords/Spears in addition to Axes as it does already, rounding it out in any duelist's kit, regardless on if they're a firebird, kensei, or another martial class.

If not Spears and Axes alone, it'd be a great addition while not breaking the skill's lore of "Extends a blade from the pole" deal. That and we even have a 'scythe'-esque polearm named Sleigher that I have been so eager to use, but sadly had no chance to do so for it does not mutate into axe, nor is supported by Ghost at all.

In which in this case I don't think it'd be so harmful to leave at full enchanting talent effectiveness, especially when that takes a few talent sub-points on top of 5 skill points from the Ghost class itself.

I don't think making it an enchant is appropriate, as it's mechanically nothing like the other enchantments. The extra 5 rounds onto duration that would give it also seems a bit overkill. An on hit dark resist reduction could be interesting, but it would definitely need to cap at more like 10-15%, certainly not 25% so it can trigger weak by itself.

I'd also say 25% is fine, solely because Aptitude + Black Beast Stamp gives just enough for that to not proc Weak!, on top of Carapace being the best Heavy Armor material, and most of the races having some sort of Darkness resistance natural of them, so it'll be fine. Best start big and if it becomes a problem, reduce it later.

We're talking about a skill that never sees the light of day for being plain bad, when compared to stuff like Ether Invitation, or Reaper Scythe.